<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>004-jQuery的核心函数$的调用.html</title>
</head>
<body>
	<div>div1</div>	
	<div id="div2">div2</div>		
	<div class="div">div3</div>
	<div class="div">div4</div>
</body>
<script src="js/jquery-1.12.4.js"></script>
<script>
	var res = $(function(){
		console.log($("div"));
		console.log($("#div2"));
		console.log($(".box"));
		console.log($("<h1>zxcxxx</h1>"));
		var oDiv = document.getElementById('div2');
		console.log($(oDiv));
		console.log('--------');
		console.log($(''));
		console.log($(0));
		console.log($(false));
		console.log($(null));
		console.log($(undefined));
		console.log($(NaN));
	})
</script>
</html>